When to Plant Sunflower in Clarke County, VA
May in Clarke County, Virginia — your action list
We've pulled the most time-sensitive tasks for Clarke County, Virginia this May and put them front and centre. Tackle them in order.
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Plant out sunflower
Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.
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Sow sunflower where they'll grow
Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.
June prep starts now
- Starting indoors: sunflower
Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.
Clarke County, Virginia is in USDA Zone 7a. The average last spring frost is April 24 and the first fall frost is October 18, giving you a growing season of approximately 177 days.
At an elevation of 1,168 feet, Clarke County receives approximately 52.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Sunflower during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.
Clarke County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.9
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Clarke County
How your county's soil matches Sunflower's growing requirements.
Soil pH
Your soil pH (5.4–6.9) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Clarke County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Sunflower.
How to Plant Sunflower
Succession Planting Sunflower
Sow every 8 weeks. Last sowing by Jul 10 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Sunflower
Sunflower needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Sunflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.3" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | — | 4.6" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.5" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 5.4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.7" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.8" | 0" | ❄️ Dormant |
| Dec | — | 4.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Clarke County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Sunflower Planting Timeline — Clarke County, VA
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | May 8 | May 8 – May 22 |
| Direct Sow | May 1 | May 1 – May 22 |
| Harvest | July 17 | Jul 17 – Sep 4 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
177 days in Clarke County
Growing Tips for Sunflower in Clarke County
Direct sow Sunflower outdoors after April 24 in Clarke County when soil has warmed and frost danger has passed.
Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Clarke County, VA?
Clarke County is in Zone 7a with an average last frost of April 24. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clarke County, VA?
Clarke County, Virginia is in USDA Hardiness Zone 7a. The average last spring frost is April 24 and first fall frost is October 18.
Your Clarke County Garden Planner — Free
A 24-page printable planner built for Clarke County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.